At the moment, has Sennheiser HD600 reduced to $249.19 Edit: Also $249 at headphones.com Thanks to Rhodey for pointing that out. See his provided link below.
Best Value Headphone - The HEADPHONE Community
Sennheiser HD 600 over-ear open-back Headphone - Official Thread - Official Headphone Model Discussion - The HEADPHONE Community
FS: Reduced to $269 Drop/Sennheiser HD6XX with extras - Buy & Sell - The HEADPHONE Community
Sennheiser HD600 Review (Headphone)
Sennheiser HD600 Review (Headphone), Page 17
Sennheiser HD600 HI-Fi Headphones : Electronics
Thou shall not resist buying HD 600 on sale directly from Sennheiser : r/ headphones
Sennheiser HD 600 - Reviews Headphone Reviews and Discussion
I finally got my 2nd HD600! : r/headphones
Sennheiser HD 600 over-ear open-back Headphone - Official Thread - Official Headphone Model Discussion - The HEADPHONE Community
Sennheiser HD600 HI-Fi Headphones : Electronics
Geekria Mesh Fabric Headband Pad Compatible with Sennheiser HD600, HD580, HD650, HD660 S, Headphones Replacement Band, Headset Head Cushion Cover Repair Part (Black) : Electronics
Sennheiser HD 600 new paint job, new pads, and new headband. This is the 3rd iteration since I purchased them back in 2010. : r/headphones
Sennheiser week] Kitchen bench HD600 in its natural habitat : r/headphones
Sennheiser HD 600 over-ear open-back Headphone - Official Thread - Official Headphone Model Discussion - The HEADPHONE Community